Twelve Principles behind the Agile Manifesto helps to make clear what it is to be Agile Software Development:
Agile first priority is to fulfill the customer need from beginning to end and continuous improvement to ad into valuable software.
Agile allow change in requirements in the late in the development as well.
Agile works on delivering software regularly interval i.e. from couple of weeks to couple of month based on project.
Close, daily cooperation between business people and developers throughout the project.
Key point is to trust, support and motivate individuals to get it projects build on time.
Daily face-to-face conversation is key point in agile testing. This is most efficient & effective way of communication.
Measuring progress by the amount of completed work.
Continually seeking excellence
Harnessing change for competitive advantage
Self-organizing team come out with best architectures, requirements, and designs.
Regular adaptation to changing circumstances with more effective way.